Of the types of degenerative lumbar spine deformities, the combination of scoliosis and spinal stenosis is one of the most disabling and progressive conditions in elderly patients. Therapeutic resignation is frequent. In spite of old age and severe osteoporosis 31 patients were treated operatively by reduction, fusion and decompression. There were 24 good results, 2 fair and one poor result. During the postoperative 30-month follow-up period (1-5 years), 4 patients died from unrelated causes. There were no serious primary complications; 3 patients had a reoperation. All patients were living independently at their homes and had a walking capacity of more than 2 km. The good overall result is attributed to the selection of patients, which is the most important factor for the outcome. Nine criteria for patient selection are listed. In multisegmental lumbar spine fusions in elderly patients, the critical areas are sacral fixation of the implant, a loss of lumbar lordosis and, if the fusion is performed from L2 caudad, vertebrae L1 and T12 being located between the lumbar spondylodesis and the stiff thoracic spine.